Barberry plant named &#39;UCONNBTCP4N&#39;

ABSTRACT

The present invention relates to a new and distinct cultivar of Barberry plant, botanically known as  Berberis thunbergii  and hereinafter referred to by the name ‘UCONNBTCP4N’. The unique characteristics of this new Barberry plant include essentially seed sterile; compact, dense, low-growing habit; thick and slightly leathery purple-red spring and summer foliage; adaptable to many landscape situations; resistant to black stem rust disease; and winter cold hardy to at least −26° C.

FEDERAL FUNDING

This invention was made with government support under 2015-31200-06009awarded by the USDA. The government has certain rights in the invention.

Background of the invention:

The present invention relates to a new and distinct cultivar of Barberryplant, botanically known as Berberis thunbergii and hereinafter referredto by the name ‘UCONNBTCP4N’.

The new Barberry plant is a product of a planned breeding programconducted in Storrs, Conn. The new barberry plant originated fromBerberis thunbergii ‘Crimson Pygmy’ (synonym Berberis thunbergii‘Atropurpurea Nana’) through the use of the mitotic inhibitor colchicineto create an autotetraploid form of the plant. Nopaternal plant isinvolved in the creation of ‘UCONNBTCP4N’. Berberis thunbergii ‘CrimsonPygmy’ is not patented and has been used in the nursery industry since1942. Briefly, nodal explants of in vitro Berberis thunbergii ‘CrimsonPygmy’ shoot cultures were exposed to 0.1% colchicine for 24 hours inliquid culture media. Nodes were then grown out in tissue culture andshoots were segregated into individual shoots and cultured further.Ploidy of individual shoot cultures was then determined by flowcytometry. Shoots converted to tetraploidy were then multiplied invitro, rooted in vitro, and acclimated to the greenhouse. Eventually,tetraploid plants were grown outdoors in containers and then in thefield. Tetraploidy was confirmed multiple times by flow cytometry whenplants were in containers and in the field.

Tetraploid plants were created in late 2004 and early 2005. Tetraploidplants were acclimated to the greenhouse, and then to outdoor containerculture in spring and summer of 2005. Tetraploid plants were grownoutdoors in containers during 2005, 2006 and 2007. In spring 2008,tetraploid plants were planted in the field for long term evaluation.Diploid Berberis thunbergii ‘Crimson Pygmy’ plants from tissue culturewere grown alongside tetraploid plants to serve as control plants.During the growing seasons of 2012, 2013, and 2014, tetraploid plantsestablished in the field were evaluated for fruit production, seedproduction, seed germination and seedling ploidy in comparison todiploid control plants.

Asexual reproduction of Berberis thunbergii ‘UCONNBTCP4N’ by eithermicropropagation via tissue culture (since 2006) or by softwood stemcuttings (since 2012) made in late June through early July in acontrolled laboratory, greenhouse or container nursery environment hasshown that the unique features of this new barberry plant are stable andreproduced true-to-type in successive generations of asexualreproduction.

SUMMARY OF THE INVENTION

Plants of the new Barberry have not been observed under all possibleenvironmental conditions and cultural practices. The phenotype may varysomewhat with variations in environmental conditions such as temperatureand light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined tobe the unique characteristics of the new Barberry plant: dense habitgrowing to 45-60 cm tall by 90-105 cm wide in 10 years; purple-redspring and summer foliage; foliage thick and slightly leathery, held onstout stems; fall foliage color is purple-red-orange; small yellow andred flowers held in clusters of 3 to 6 flowers, in late April-early May,sometimes cymous; fruit is red, ripening in October, ellipsoidal, 7-10mm long and 4-5 mm wide; cold hardy in winter to at least −26° C.; seedproduction is 0.2% that of standard, diploid Berberis thunbergii‘Crimson Pygmy’, so it is essentially seed sterile; tested to beresistant to black stem rust by the USDA Cereal Diseases Laboratory inSt. Paul, Minn.

These characteristics in combination distinguish Berberis thunbergii‘UCONNBTCP4N’ as a new and distinct Barberry plant:

-   -   1. essentially seed sterile;    -   2. compact, dense, low-growing habit;    -   3. thick and slightly leathery purple-red spring and summer        foliage;    -   4. adaptable to many landscape situations;    -   5. resistant to black stem rust disease; and    -   6. winter cold hardy to at least −26° C.;

Plants of the new Barberry can be compared to plants of the femaleparent Berberis thunbergii ‘Crimson Pygmy’. Plants of the new Barberrydiffer primarily from plants of Berberis thunbergii ‘Crimson Pygmy’ inthat Berberis thunbergii ‘UCONNBTCP4N’ is essentially sterile, whilesame age ‘Crimson Pygmy’ plants produce over 8,000 seeds per plant peryear. In addition, Berberis thunbergii ‘UCONNBTCP4N’ grows approximately10% larger than ‘Crimson Pygmy’ and has stouter stems and thicker, moreleathery foliage.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the overall appearanceof the new Barberry plant showing the colors as true as it is reasonablypossible to obtain in colored reproductions of this type. Colors in thephotographs may differ slightly from the color values cited in thedetailed botanical description which accurately describe the colors ofthe new Barberry plant.

FIG. 1 is a photograph showing a field grown plant of ‘UCONNBTCP4N’ asit appears in spring (top image) and then later in the summer (bottomimage).

FIG. 2 is a photograph showing a close up of ‘UCONNBTCP4N’ foliage inthe spring prior to long shoot extension.

FIG. 3 is a photograph showing a close up comparison of leaves from‘Crimson Pygmy’ (left column) and ‘UCONNBTCP4N’ (right column).

FIG. 4 contains photographs showing the flowers of ‘UCONNBTCP4N’.

FIG. 5 contains photographs showing the intact fruits of ‘Crimson Pygmy’(left) and ‘UCONNBTCP4N’ (right) in the top panel. The bottom panelshows fruits cut open to reveal ovary contents. Well-developed seeds arepresent in ‘Crimson Pygmy’ fruits (left), but seeds have aborted at anearly stage within the fruits of ‘UCONNBTCP4N’ (right).

FIG. 6 is a photograph showing three container grown plants of‘UCONNBTCP4N’ at the beginning of their second summer of growth sincepropagation. These plants were rooted from softwood cuttings two summersprior.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs and following observations, measurementsand values describe plants grown during the spring, summer, or fall inground beds or container, in an outdoor nursery in Storrs, Conn. andunder cultural practices which closely approximate commercial Barberryproduction. Plants used for most photographs and description were 10years old. In the following detailed description, color references aremade to The Royal Horticultural Society Colour Chart, 1995 Edition,except where general terms of ordinary dictionary significance are used.

-   Botanical classification: Berberis thunbergii ‘UCONNBTCP4N’.-   Parentage:    -   -   Female, or seed, parent.—Barberry thunbergii ‘Crimson Pygmy,            not patented.        -   Male, or pollen, parent.—Not applicable. Mitotic inhibitor            colchicine was used to create an autotetraploid from a            maternal parent only.-   Propagation:    -   -   Type.—softwood stem cutting.        -   Time to initiate roots, summer.—About 6 weeks at daytime            temperatures between 75-90° F.        -   Time to produce a rooted young plant, summer.—About 8-12            weeks at temperatures between 75-90° F.        -   Root description.—2-6 roots per cutting, yellow in color.        -   Rooting habit.—fibrous root system develops from the initial            adventitious roots.-   Plant description:    -   -   Plant form and growth habit.—low, dense, mounded plant with            many branches, typically wider than tall.        -   Plant height.—About 45-60 cm tall in 10 years.        -   Plant diameter (area of spread).—About 90-105 cm wide in 10            years.-   Lateral branch description:    -   -   Length.—About 15 cm, typically between 10-20 cm.        -   Diameter.—About 2 mm to 3 mm.        -   Internode length.—About 15 mm, typically between 10-20 mm.        -   Aspect.—upright and arching outward from the plant center.        -   Strength.—firm and stiff.        -   Texture.—fine.        -   Color.—Close to 146D yellow-green (new, current. season            shoots).        -   Thorns.—Quantity: single at most nodes. Length: 10-12 mm.            Width at the base: 1 mm. Color: 146D at base, changing to            183 B at tip. Texture: slender, fine.-   Leaf description:    -   -   Arrangement.—whorled in rosette on spur shoots; alternate            down long shoots, but typically 2-3 leaves at each node.        -   Length.—About 35 mm, typically ranging from 20-50 mm.        -   Width.—About 18 mm, typically ranging from 14-21 mm.        -   Shape.—obovate to spatulate-oblong.        -   Apex.—typically obtuse, sometimes with small spine at tip.        -   Base.—narrowing to only petiole; very acute.        -   Margin.—entire.        -   Texture, upper and lower surfaces.— glabrous.        -   Venation pattern.—pinnate.        -   Color.—Developing leaves, upper surface: Close to 183A and            183B greyed-purple group under high light conditions.        -   Developing leaves, lower surface.—186A greyed purple group            at margins, changing to 191B greyed green in center under            high light conditions.        -   Fully expanded leaves, upper surface.—Close to 187A            greyed-purple group and 200A brown group under high light            conditions. Shaded leaves 137A green group.        -   Fully expanded leaves, lower surface.—Close to 191A            greyed-green group under high light conditions. Shaded            leaves 137C green group.        -   Petiole.—Length: About 1-14 mm. Diameter: About 1 mm.            Texture, upper and lower surfaces: glabrous. Color, upper            and lower surfaces: same as for leaf lamina.-   Flower description:    -   -   Flower arrangement and habit.—typically cymous.        -   Fragrance.—minimal.        -   Natural flowering season.—April in Storrs, Conn.        -   Flower longevity.—7 to 14 days depending on weather            conditions.        -   Inflorescence length.—About 15 mm; ranging from about 10-20            mm.        -   Inflorescence diameter.—About 22.5 mm; ranging from about            21-25 mm.        -   Flower diameter.—About 12 mm; ranging from 10-13 mm.        -   Flower length (height).—About 5.75 mm; ranging from 5-7 mm.        -   Flower buds.—Length: About 4 mm. Diameter: About 6 mm.            Shape: Rounded. Color: Close to 53A and 53B, red group.        -   Petals.—Arrangement: 6 petals in a single whorl.        -   Length.—About 4-5 mm.        -   Width.—About 3-4 mm.        -   Shape.—cupped.        -   Apex.—rounded to acute.        -   Margin.—smooth.        -   Texture, upper and lower surfaces.—both glabrous.        -   Color.—When opening and fully open, adaxial and abaxial            surfaces: 12C yellow group.        -   Sepals.—Arrangement: 6 to 8 sepals in a single whorl.            Length: About 7 mm. Width: About 4 mm. Shape: cupped. Apex:            rounded to acute. Base: straight-sided, tapering. Margin:            smooth. Texture, upper and lower surfaces: glabrous. Color:            Fully developed, adaxial surface: Close to 12C, yellow            group, with colors from abaxial side showing through. Fully            developed, abaxial surface: Close to 53A and 53B, red group.        -   Peduncles.—Length: About 4-14 mm. Diameter: About 1 mm.            Aspect: About 60 degrees from lateral branch axis. Color:            Close to 53A and 53B, red group.        -   Pedicels.—Length: About 4-6 mm. Diameter: About 1 mm.            Aspect: About 45-60 degree from peduncle axis. Color: Close            to 53A and 53B, red group.        -   Reproductive organs.—Stamens: Quantity: 6. Anther shape:            flat to cupped, narrow. Anther length: About 4 mm. Anther            color: Close to 12C. Pollen amount: Scarce and sticky.            Pistils: Quantity: 1 per flower. Pistil length: About 3 mm.            Style length: About 1-2 mm. Style color: Close to 144C and            145B. Stigma color: Close to 144C and 145B. Ovary color:            Close to 144C and 145B. Seeds and fruits: Seed and fruit            development have been observed on plants of the new            Barberry. Fruits are almost always devoid of seeds.            ‘UCONNBTCP4N’ produces only 0.2% of the seed produced by            ‘Crimson Pygmy’, even if fruits are produced.-   Garden performance: Plants of the new Barberry have been observed to    have excellent garden performance and tolerate a wide range of    environmental conditions and temperatures ranging from about −26*C    to about 40° C.-   Pathogen & pest resistance: Plants of the new Barberry have been    observed to be resistant to blackstem rust. Plants of the new    Barberry have not been shown to be resistant to pests and other    pathogens common to Barberry plants.

It is claimed:
 1. A new and distinct Barberry plant named ‘UCONNBTCP4N’as illustrated and described.